Apprentice
apothecary. Carl Scheele was born December
9, 1742, one of eleven children. He received very little formal education
and no training whatsoever in science. At age 14, Scheele became
an apprentice apothecary of the firm Martin Anders Bauch in Gothenburg.
The supply of chemicals present in the pharmacy afforded Scheele with a
starting point for many investigations and discoveries. He also made
use of the numerous scientific books of the day. In 1765 Bauch sold
the business and Scheele took a position with Kjellström in Malmö
where he was again allowed to experiment. In 1768, Scheele moved
to Stockholm and again worked in a pharmacy. Here he and Anders Johan
Retzius isolated tartaric acid from cream of tartar. The results
were published in 1770.

Fire
Air. In 1770, Scheele moved to Uppsala
where he became the assistant in the laboratory of Lokk. It is here
that Scheele discovered 'fire air' [oxygen] sometime before
1773. He produced fire air several ways. In the
first method, he reacted (using modern names) nitric acid with potash (KOH
and/or K2CO3)
which formed KNO3). Distilling
the residue with sulfuric acid produced both NO2
and O2. The former was
absorbed by Ca(OH)2(sat'd), leaving
oxygen (fire air). He also obtained fire air from strongly
heating HgO and MnO2 and by heating
silver carbonate or mercuric carbonate and then absorbing the CO2
by alkali (KOH):

AgCO3(s)
Ag(s) + CO2(g) + O2(g)

Recognition
in Sweden. On February 4, 1775, Carl
Scheele was elected to membership into the Royal Academy of Sciences.
This great honor (with the King of Sweden was in attendance) had never
before (and never since) been given to a student of pharmacy.

Köping.
In 1775, Carl Scheele moved to Köping, Sweden where he took a position
as superintendent of the pharmacy. By now Scheele was receiving various
offers for improved positions from around Sweden. The town of Köping
did not want to lose their new famed son so they obtained for him his own
pharmacy, previously owned by an apothecary named Pohls who had died.
Pohls's widow remained in Köping to manage Scheele's household.
It is believed that Scheele did not travel from Köping, but rather
spent his time engaged in his scientific pursuits.

"Oh,
how happy I am! No care for eating or drinking or dwelling, no care
for my pharmaceutical business, for this is mere play to me. But
to watch new phenomena this is all my care, and how glad is the enquirer
when discovery rewards his diligence; then his heart rejoices"1

Communication
problems. In eighteenth Century Europe,
the art of communicating one's results was primitive by today's standards.
Often scientists used personal letters describing results to contemporaries
interested in the same work. Scheele was isolated from much scientific
literature although he did communicate with Lavoisier who sent him a copy
of his early book. Writing a book was the best way to disseminate
results, however, it often took years to accumulate enough results for
a book and then it could take years longer for the book to be published.
Such was the tragedy of Carl Scheele who discovered oxygen (fire air)
two years before Priestley. Scheele's book, Chemical Treatise
on Air and Fire, was not published until 1777, by which time European
scientists were aware of Priestley's discovery of the same gas (dephlogisticated
air) in 1774. At the time of his death, very little was known
of Scheele's life, the poverty in which he lived, the cold in which he
worked, his struggle with illness and his early death. Over a century
passed before two individuals, working with Scheele's notes, papers and
letters held by the Swedish Royal Academy of Sciences, brought to the public
in 1892 the important scientific contributions of Carl Scheele.2

An 'airbag'
used by Scheele

Cyanide
and marriage vows. At Köping,
Scheele prepared compounds of cyanide, including gaseous hydrogen cyanide,
and even described its taste! He also studied a variety of arsenic
compounds. Without proper ventilation, Scheele was frequently exposed
to deadly poisons. It is thought that this exposure seriously damaged
Scheele's health and significantly shortened his life. Scheele was
aware of the cause of his poor health and he referred to it as "the
trouble of all apothecaries." Carl Scheele died at
age 43 on May 26, 1786. Two days before he died, he married the widow
Pohls so that she would inherit the pharmacy and his belongings.

Lasting
accomplishments.

• Few,
if any chemists have discovered more new simple substances than Scheele.
He is credited with: